I accidentally deleted some of my photos in iPhone. How can I get back? Thank you

Did you check the recently deleted album to see if they are there?

Follow this link

Restore your iPhone, iPad, or iPod touch from a backup

Learn how to restore your device from a backup in iCloud or on your computer.

https://support.apple.com/en-ca/HT204184

Did you download them anywhere? If not, they are gone.

Did you do an iCloud backup before you deleted the pictures? If so, restore it to your phone.

You can use third party software and do a data recovery and get them back such as fonepaw data recovery

Use third party software to do a data recovery such as fonepaw data recovery